If diagram 2 represents the paragon, diagram
3 attempts to display the practice by refining the circuit with
indications of effectiveness.[66]The
unbroken lines indicate accountability relationships which, whilst
not unproblematic, are argued to be reasonably robust. The broken
lines reflect relationships which, despite their strengths, possess
inherent limitations. The question marks signify the contentious
nature of some of these classifications, but it is argued that
such categorisations facilitate debate and analysis. For example,
the inability of the House of Lords to act as a significant check
on the core executive is due to both its limited powers of oversight
and revision and also its lack of democratic legitimacy.